Safety control apparatus for



April 1935- G. HEGWEIN 2,037,684

SAFETY CONTROL APPARATUS FOR GAS BURNERS Filed July 28, 1955 Fig.2 P

Inventor Giw Hag menu 1W1 ma lei Art-ways Patented Apr. 14, 1936 UNITE-D STATES SAFETY CONTROL APPARATUS FOR GAS BURNERS Georg Hegwein, Stuttgart, Germany, assignor to Junkers & 00. G. m. b. H., Dessau, Germany Application July 28, 1933, Serial No. 682,717 In Germany September 6, 1932 7 Claims.

The present invention relates to safety control apparatus for gas burners.

Safety control apparatus for gas burners have already been proposed in which a pilot-burner, 5 whose valve, which is influenced by the heat of the pilot-flame, shuts oil the main gas current and simultaneously also shuts off the supply of gas for the pilot-flame when the pilot-flame is extinguished. Hitherto the pilot-burner has been 10 arranged separate from the main gas pipe andconnected to it by a separate branch pipe so that the pilot-burner, as well as the necessary valve-rod, was easily liable to be damaged or destroyed.

15 The present invention improves and simplifies this safety device by the pilot-bumer being intercalated in the main gas pipe, and its casing being formed as a passage for the main gas current.

20 An example. of construction of the invention is shown in the accompanying drawing, in which:-

Figure 1 is a view partly in side elevation and partly in vertical section, the section being taken on the line l--| of Fig. 3, except that Fig. 1 shows 5 certain valve operating parts along the section line in elevation;

Figure 2 is a section on the line 22 of Fig. 1; and

v Figure 3 is a top plan view of a portion of the go construction shown in Figure 1, except that in Figure 3 the valve operating part 32 is shown in ."cross-section.

. The casing l3 of a safety pilot-burner is inter- 1 isolated between a gas supply pipe l and a pipe 35 fllfleading to a number of burners l I. The casing l3isclc$ed externally by a thermostat disc or 'ex'pan'sible diaphragm lifi, to which is secured a 1 m j g'as valve it, which controls a valve passage.

I lln, pilot-burners which are arranged separate 4of'rom the main pipe, it is already known to close the pilot-burner casing externally by 2. diaj which operates a valve controlling the 1p rnergas pipe. The diaphragm I5 is pressedwith its edge against the casing l3 by 45 m'eafis'of a ring l4. and is provided with an opening l 8 for a pilot-flame l9, and with openings 20 for some small heating flames 2|. 22 is a leafspring, which bears with its bent ends against the diaphragm I5 and tends to press the valve- 50 body l6 on to its seat. A plate 23 placed in front of the heating flame openings 23 separatesv ofi a pace or chamber 24, which is in communication by a throttle opening 25 with a chamber 26 behind the diaphragm I5. By the throttling of the 55 heating gas the heating flame becomes short and broad and thereby more effective in heating the diaphragm. From the valve passage H a pas sage 21 branches oil in advance of the valve member l6 and leads to a chamber 28, arranged in 60 the casing l3 of the pilot-burner, and the outlet of which is controlled by an ignition valve 29, which is pressed on to its seat by a spring 30. The ignition valve 29 is actuated by a cam 33 on a bolt 32, which is fltted with a handle 3|. The cam 33 co-operates with the valve-rod 34 5 oi. the ignition-valve 29, and raises the ignition valve from its seat on the rotation of the bolt 32. The end of the bolt 32 is made as a controlling cock 35, or connected with a controlling cock, by which the quantity of the gas flowing to the burners ll and thus the size of the flames can be adjusted. The outlet of the gas pipe in the pilotburner casing l3 serves at the same time as a casing for the controlling cook 35, so that the controlling cock, main valve, and ignition valve are combined in the casing l3 of the pilot-bumer. A throttle 31, fitted with a filter 36, in advance of the valve passage l'l limits the maximum quantity of gas flow per unit of time from the gassupply pipe ID to the passage l'l for a given gas pressure in the gas supply, and can be conveniently introduced from the outside into the casing inlet through a passage 38. The passage 38 is closed by a closure screw 39.

The mode of operation of the apparatus is as follows:-

If the pilot flame l9 goes out, the cooling diaphragm l5 presses the main valve member IE on to its seat, and thus shuts oil both the main gas and the pilot burner gas. If the pilot-burner is 30 to be again ignited, the bolt 32 is turned to such an extent by means of the handle 3! that the cam 33 raises the ignition valve from its seat. The ignition gas can now pass through the passage 21 and the chamber 28 into the chamber 26 be- 35 hind the diaphragm l5, from which it emerges through the pilot-flame opening I8 and heating flame openings 20. By the heat of the flames of the ignition gas the expansible diaphragm I5 is quickly heated, becomes curved, and thereby opens the valve passage l'l, so that the main gas flows through the throttle 31 into the chamber 26, the outlet of which at first is still closed by the controlling cook 35. When the cam 33 is brought out of engagement with the valve mem- 5 ber 29 by turning the bolt 32 in the reverse direction, the spring 30 closes the ignition valve 29. By further rotating the rod 32, the controllingcock 35 is brought into the open position, whereupon the gas flows to the burners l I and on emerging irom'the burners is ignited by the pilotflame I9. The flames are large or small according to the position of the controlling cock 35.. Ii'for any reason the pilot-flame becomes extinguished, the diaphragm l5 cools down, and again forces the valve member l6 on to its seat, whereby the whole gas supply is again shut ofi. By the combination of all the essential parts (controlling cook 35, main valve l6 and ignition valve 29), in the casing l3 of the pilot-burner,

and by the insertion of the pilot-burner in the main gas line, the handling operation is simpli fled and security in working increased.

I declare that what I claim is:

1. Safety control apparatus for gas burners comprising the combination with a main gas burner and a main gas line for said main gas burner, of a casing interposed in said main gas line and having an inlet passage and an outlet passage so connected to said main gas line on opposite sides of said casing as to restrict the supply of all gas to said main gas burner to a flow through said casing from said inlet passage to said outlet passage, a thermostatic expansible diaphragm forming a closure for said casing and having at least one pilot burner opening therein and a main gas valve in said casing and connected to said diaphragm to govern the connection between said inlet and outlet passages and adapted to supply gas to said pilot burner opening, the said diaphragm having its inner face subject to contact therewith of the gas stream through said casing and its outer face exposed to the pilot flame and operating to shut oil? the gas supply to said outlet passage and to the pilot burner opening when the pilot flame is extinguished.

2. Safety control apparatus for gas burners comprising the combination, with a main gas burner and a main gas line for said main gas burner, of a valve casing interposed in said main gas line adjacent said main gas burner and having an inlet passage and an outlet passage so-connected to said main gas line on opposite sides of said casing as to restrict the supply of all gas to said main gas burner to a flow through said casing from said inlet passage to said outlet passage, a main gas valve in said casing operating to open and close said inlet passage, a pilot burner mounted in one wall of said casing on the outlet side of said main gas valve and arranged to be fed from the gas flowing into said casing through said inlet passage when said main gas valve is open, a thermostatic element operatively associated with said pilot burner and connected with said main gas valve to operate said main gas valve in a manner to open said inlet passage to the flow of gas into and through said casing when the pilot flame is on and to close said inlet passage and thereby cut off the supply of gas to said outlet passage and to said pilot burner when the pilot flame is extinguished, said thermostatic element having one side portion thereof exposed to direct contact therewith of the gas flowing through said casing from said inlet to said outlet passage and another side portion exposed to the heat of the pilot flame. a by-pass in a wall of said casing leading from said inlet passage on the inlet side of said main gas valve to said pilot burner for feeding gas to said pilot burner when said main gas valve is closed and a manually operable valve for controlling said bypass.

3. Safety control apparatus for gas burners comprising a main valve casing having an inlet passage for the supply of gas thereto and an outlet passage adapted to be connected to a main gas burner, an apertured thermostatic disc so arranged as an outer wall portion of said casing between said inlet and outlet passagesas to expose the inner face of said disc to contact therewith of the main gas stream in said casing and also form a pilot jet fed from said gas stream in said casing and a main gas valve for said inlet passage operatively connected to said thermostatic disc, said disc having its outer face exposed to the pilot flame and operating to cut ofl the gas supply to said outlet passage and to said pilot jet when the pilot flame is extinguished.

4. Safety control apparatus for gas burners comprising a main valve casing having an inlet passage for the supply of gas thereto and an out let passage adapted to be connected to a main gas burner, an apertured thermostatic disc so arranged as an outer wall portion of said casing between said inlet and outlet passages as to expose the inner face of said disc to contact therewith of the gas flowing through said casing from said inlet to said outlet passage and also form a pilot jet fed from said gas flow in said casing, a main gas valve for said inlet passage operatively connected to said thermostatic disc, said disc being influenced by the pilot flame to operate said main gas valve in a manner to open said inlet passage to the flow of gas into and through said casing when the pilot flame is on and to close said inlet passage and thereby shut off the supply of gas to said outlet passage and to said pilot jet when the pilot flame is extinguished, a by-pass wholly within said main valve casing about said main gas valve from the inlet to the outlet side thereof and a manually operable by-pass valve for supplying gas to said pilot jet when said main gas valve is closed.

5. Safety control apparatus for gas burners comprising the combination, with a main gas burner, and a main gas line for said main gas burner, of a valve-casing interposed in said main gas line adjacent said main gas burner and having an inlet passage and an outlet passage so connected to said main gas line as to restrict the supply of all gas for said main gas burner to a flow through said casing from said inlet passage to said outlet passage, an apertured thermostatic disc so arranged as an outer wall portion of said casing between said inlet and outlet passages as to expose the inner face of said disc to contact therewith of the main gas stream in said casing and also form a pilot jet adapted to be fed from said main gas stream in said casing, a main gas valve for said inlet passage operatively connected to said thermostatic disc, said disc having its outer face exposed to the pilot flame and operating said main gas valve in a manner to cut off the gas supply to said main gas burner and said pilot jet when the pilot flame is extinguished, and manually operable control means arranged in said casing adapted to govern the rate of gas flow to said main burner.

6. Safety control apparatus as defined in claim 5 and further characterized by a by-pass in said casing around said main gas valve from its inlet to its outlet side for feeding gas to said pilot jet when said main gas valve is closed and a valve for said by-pass operatively connected with said manually operable control means.

7. Safety control apparatus as defined in claim 5 and in which said manually operable control means comprises a cockin said outlet passage of said valve casing, said valve casing being provided with a by-pass around said main gas valve from its inlet to its outlet side for feeding gas to said pilot jet when said main gas valve is closed, a valve for said by-pass and a common manual control for said by-pass valve and said cock.

GEORG HEGWEIN. 

